Did you get a suitable reply from anyone? 

I signed up for Afterpay after making one successful purchase of a book on EBay, with no issues. Now when I try to make purchases on EBay it won't go through. This keeps happening. Already made a complaint about this and got an answer that amounted to "Yes this can happen."
If it happens again and I end up paying from my savings then Afterpay is useless to me and I may as well cancel my account.
It would be great to get a straight answer from them as to why it's happening.